Update BoundedReader.java

https://docs.oracle.com/javase/8/docs/api/java/io/Reader.html
Add read bytes EOF test

Patch by zhanhb <zhanhb88@gmail.com>, applied unmodified

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/io/trunk@1746612 13f79535-47bb-0310-9956-ffa450edef68

Author: krosenvold

src/main/java/org/apache/commons/io/input/BoundedReader.java

@@ -139,7 +139,7 @@ public int read( char[] cbuf, int off, int len ) throws IOException {
         for ( int i = 0; i < len; i++ ) {
             c = read();
             if ( c == -1 ) {
-                return i;
+                return i == 0 ? -1 : i;
             }
             cbuf[off + i] = (char) c;
         }

src/test/java/org/apache/commons/io/input/BoundedReaderTest.java

@@ -181,4 +181,12 @@ public void close()
         mr.close();
         assertTrue( closed.get() );
     }
-}
+
+    @Test(timeout = 5000)
+    public void testReadBytesEOF() throws IOException {
+        BoundedReader mr = new BoundedReader( sr, 3 );
+        BufferedReader br = new BufferedReader( mr );
+        br.readLine();
+        br.readLine();
+    }
+}